Electrically operated compressor



March 11, 1952 J. P. NORTON 2,538,753

ELECTRICALLY OPERATED COMPRESSOR Filed June 25, 1948 2 SHEETSSHEET l A Home March 11, 1952 NORTON 2,588,753

ELECTR ICALLY OPERATED COMPRESSOR Filed June 25, 1948 2 SHEETS-SHEET 2 lmu'ulur Patented Mar. 11, 1952 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to a novel compressor adapted to be used in compressing gases, liquids or air and which is readily capable of use in refrigerating systems for pumping gases or liquids or for supplying compressed air.

A primary object of the present invention is to provide a compressor having a motor as an integral part thereof thereby eliminating the use of a conventional motor for driving the compressor together with the driving connections such as pulleys, belts, couplings or gears.

Another object of the invention is to provide a compressor having a motor as an integral part thereof and which may be much more economically manufactured and sold than a conventional compressor with a separate motor, which will be much lighter in weight, require less materials and utilize less space.

Still a further object of the invention is to provide an electrically operated compressor of extremely simple construction utilizing asolenoid means for actuating a reciprocating pumping element for pumping and compressing a medium and wherein the reciprocating motion of the pumping element is converted to a rotary motion for operating a commutator employed for controlling the flow of the electric current to the solenoid means of the device.

Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, illustrating the presently preferred embodiment thereof, and wherein:

Figure 1 is a side elevational view, partly in vertical section of the electrically operated compressor;

Figure 2 is a side elevational view of the commutator thereof;

Figure 3 is an end elevational view of the compressor looking from left to right of Figure 1;

Figures 4, and 6 are sectional views taken substantially along planes as indicated by the lines 44, 5-5, and 66, respectively, of Figure 2, and

Figure '7 is a perspective view of one of the brushes of the commutator.

Referring more specifically to the drawings, the novel compressor in its entirety is designated generally 8 and includes a hollow base, designated generally 9 formed of the sections l0 and H and having abutting external flanges 12 for receiving fastenings 53 for detachably connecting the base sections and H. Each of said sections I0 and II are provided with one or more depending supporting legs 14 for engaging a supporting surface I5 in which the legs are preferably detachably secured, by any suitable means, not shown. The base 3 is provided with opposite upstanding walls having aligned openings 16 for receiving spaced portions of a crankshaft I! which portions are journaled in bearings l8 supported by internal annular flanges [9 of said walls. The base 9 forms a hollow chamber 20 in which the crank 2| of the crankshaft I1 is rotatably disposed and to which is connected one end of a piston rod 22.

A cylinder 23 is provided with an externally flanged lower end 24 which is secured by fastenings 25 to the top wall of the base 9 around an opening 26 thereof which registers with the bore of the cylinder 23 through which the piston rod 22 loosely extends. A relatively thick walled piston 21 is reciprocally disposed within the cylinder 23 and is connected to the upper end of the piston rod 22.

The upper, externally flanged end 28 of the cylinder 23 is closed by a cylinder head, designated generally 29 which is detachably secured by fastenings 30 to the external flange thereof and which is composed of superposed bottom and top sections 3! and 32. The sections 3| and 32 are provided with connecting passages forming an inlet port 33 the inner portion of which is enlarged to accommodate a ball valve 34 which is normally urged upwardly and to a closed position by an expansion spring 35 which seats against a perforated stop 36 which is detachably mounted in the lower, inner end of said inlet port 33 so that the valve 34 will admit a medium to be compressed, such as a gas, liquid or air to the upper end of the cylinder 23 but which will prevent such medium from escaping from the cylinder 23 through the port 33. The upper section 32 is externally enlarged to form with the section 3| a chamber 31 which communicates with the cylinder 23 through a port 38 formed in the section 3| and which port is normally closed at its upper end by a valve 39 which is disposed in the chamber 31 and has an upwardly projecting valve stem 40 which is reciprocally guided in a downwardly opening recess 4| of the head section 32 and which carries a spring 43 which normally urges the valve 39 downwardly and into a closed. position. The cylinder head section 32 is provided with an outlet port 44 which communicates with the chamber 31 and which is adapted to be connected to a conduit 45 connected with suitable means, not shown, to which the compressed medium is adapted to be supplied.

The cylinder 23 is formed of a non-magnetic metal and the piston 21 is formed of iron. The cylinder 23 is surrounded by relatively long upper and lower solenoids 46 and 41, respectively, between which is interposed a smaller, intermediate solenoid 48.

A fiywheel 49 is fixed to one end of the crank shaft I1, externally of the base 9 and a commutator 50 is fixed to the opposite end of said crankshaft, also externally of the base 9. The commutator 50 comprises a body formed of an electrical insulating material the periphery of which is recessed to accommodate a strip 52 of an electrical conducting material, preferably copper and which has a continuous central portion 53 extending entirely therearound and around the body 5i and staggered side edge portions 54 and 55, the ends of which are spaced slightly from one another circumferentially and each of which extends through an are slightly less than a half circle and approximately equal to 178. A plate 56 is supported on the outer side of the wall of the base 9 which is located adjacent the commutator 50 by means of rods 51 having threaded ends which extend through apertured extensions of said plate 56 and into threaded recesses '58 of the base 9. One of the rods 51 is disposed above the level of the commutator 5D for supporting three brush elements 59, 60 and fil each of which is provided with a pair of supporting arms 62 forming integral extensions of a cross bar or bight portion 63 to which the brush element is connected. The pairs of legs 62 are 'apertured adjacent their free ends for pivotally engaging said upper rod 51 and are held in properly spaced relationship to one another by spacer sleeves 64 which, together with said arms 62 are held applied to said upper rod 51 by a cotter pin 65. The brush 59 is disposed to contact the uninterrupted intermediate portion 53 of the conductor strip 52, the brush 60 contacts the conductor strip portion 54 only during a portion of each revolution of the commutator 50 and the brush 6| contacts only the conductor strip portion 55 during another portion only of each revolution of the commutator. The brushes 59, 60 and 6! will be held by gravity in engagement with either the commutator body 5| or the strip 52. A single contact brush 66 which is disposed beneath and in vertical align ment with the brush 59 contacts the intermediate portion 53 of the strip 52 at all times during rotation of the commutator56 and is provided with more widely spacedarms 61 forming extensions of an intermediate cross piece 68 to which the brush 66 is attached. The-arms 61. may be rigidly supported onthe other, lower rod 51 by spacer sleeves 69 and retained thereon by a cotter pin or suitable spring means, notshown, may be provided for urgingthe brush 6.6..into engagement with the conductor strip 52., V

The brush 66 is connected to an electrical conductor H preferably extending from the positive side of a source of electric current such as a storage battery 12. The brush 59 is connected by a conductor 13 to the intermediate solenoid 48. A conductor 14 connects the brush 60 to the upper solenoid 46 and a conductor connects the brush iii to the lower solenoid 41. The solenoids 48, 46 and 41 are connected by conductors 16, 1! and 18, respectively, to the negative side of the battery 12 to complete the electric circuit.

Assuming that the inlet port 33 isconnected to a source of supply of a liquid or gaseous medium to be compressed, not shown, or open to the atmosphere as illustrated for compressing air, and assuming that the piston 2'! is in its uppermost position of Figure 1, in this position the brush 60 will have moved out of contact with the conductor portion 54 and the brush 6! will be approaching a position for movement into contact with the conductor portion 55. The inertia of the fiy-wheel 49 will carr the crank 2! past this uppermost dead center position so that the brush 6| will contact the conductor strip portion 55 in which positions the solenoids 4?, 48 will function as a unit for attracting the iron piston 21 which constitutes the core to draw said piston downwardly. During the downstroke of the piston 21 the valve 39 will be closed and the valve 34 will be drawn open to admit the medium to be compressed into the cylinder above the piston in response to the vacuum created by the downstroke of the piston. As the piston approaches the lower extremity of its movement the conductor strip portion 55 will move out of contact with the brush BI and the flywheel will carry said piston and crank 2! slightly past their lowermost dead center positions and until the conductor strip portion 54 contacts the brush 69 whereupon the upper solenoid 46 will be energized to function with the intermediate solenoid 48 as a single unit for drawing the piston 21 upwardly and back to its position of Figure 1. During the upstroke of the piston 21 the inlet valve 34 will be held in a closed position and the valve 39 will be unseated for expelling the compressed medium through the outlet port 38, chamber 3! and passage 44 into the conduit 45. As the piston 21 substantially reaches the upper extremity of its movement, the operation previously described will be repeated.

It will thus be readily apparent that an extremely simple compressor has been provided wherein the prime mover constitutes an integral part thereof.

Various modifications and changes are contemplated and may obviously be resorted to, without departing from the spirit or scope of the invention as hereinafter defined by the appended claim.

I claim as my invention:

A self-starting solenoid control means comprising a cylinder, a pair of solenoids disposed one around each end of the cylinder, a piston reciprocably mounted in the cylinder and formed of a material capable of being attracted by an energized electromagnet, a rotary electric switch adapted to be interposed in an electric circuit of the solenoids including spaced conductor portions one connected to each solenoid for alternately energizing the solenoids and for maintaining each solenoid energized during a portion of rotation of the switch equal to slightly less than one-half of a complete revolution, means forming a driving connection between the piston and switch whereby the switch will complete one rev.- olution to each two strokes of the piston, said switch rotating in timed relationship to the reciprocating movement of the piston for de-energizing each of the solenoids as the piston approaches its extremity of movement in a direction toward said solenoid and for thereafter energizing the other solenoid to move the piston in the opposite direction, and a third solenoid disposed around the cylinder between the first mentionedsolenoids and adapted to be constantly energized by the electric current source for func tioning with either of the first mentioned solenoids, when energized, and functioning when 5 both of the first mentioned solenoids are deenergized to move the piston from a substantially dead center position at either extremity of its movement toward a position intermediate of its extremities of movement whereby the rotary switch is moved, by movement of the piston from either extremity of its movement, into a position to energize the first mentioned solenoid, disposed remote to the piston, to thereby provide a selfstarting unit.

JAMES P. NORTON.

REFERENCES CITED The following references are of record in the file of this patent:

Number 10 Number 6 UNITED STATES PATENTS Name Date Darling Feb. 8, 1887 Birkin Mar. 21, 1893 Hicks Oct. 6, 1896 Conly Aug. 8, 1899 Hargrove Dec. 22, 1925 FOREIGN PATENTS Country Date Great Britain May 22, 1936 Denmark Mar. 6, 1933 

